Issued Patents All Time
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 6925178 | Returning ringing signals through the tip amplifier of subscriber-line interface circuitry | John Gammel, David Paul Chabinec | 2005-08-02 |
| 6333664 | Low operating power, high voltage ringing switch circuit | — | 2001-12-25 |
| 6169425 | Voltage sensing current foldback switch circuit | Dewayne A. Spires | 2001-01-02 |
| 5631797 | Overvoltage protector | David Paul Chabinec | 1997-05-20 |
| 5532498 | High sensitivity control circuit for optical solid-state relays | Craig B. Ziemer | 1996-07-02 |